What is the Substance Library for?

It's where your reusable chemical substances and mixtures live — each with its CAS number (or, for substances that don't have one, just a chemical name), hazard codes, and GHS pictograms. Substances and Mixtures are kept on separate tabs 1, and you can add a new one anytime 2, so you can reuse it across multiple SDS documents instead of re-entering the same ingredient data every time. Note: the Substance Library isn't included on the Basic plan — Standard or higher is required, and Basic accounts are shown an upgrade prompt if they try to open it.